resonator. n. 1. (Electronics) any body or system that displays resonance, esp a tuned electrical circuit or a conducting cavity in which microwaves are generated by a resonant current.. resonator-a hollow chamber whose dimensions allow the resonant oscillation of electromagnetic or acoustic waves. cavity resonator, resonating chamber. chamber-a natural or artificial enclosed space. soundbox, body-a resonating chamber in a musical instrument (as the body of a violin).
The other method of classifying the modules is by their bandwidth rating in megabytes per second. 1600MHz memory can run at a theoretically speed of 12.8 gigabytes per second or 12,800 megabytes per second.
The higher the number at the end, the faster the memory. So GDDR5 is the fastest of those three (and it's usually a multiplier - so GDDR5 is 5x data rate whereas DDR3 is only 3x). The G is supposed to signify designed for GPUs, but often just is added for graphics cards with no real change in design.